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How do I perform the SQL Join equivalent in MongoDB?
...background as well, I would appreciate MongoDB taking a 'result set' (with selected returned fields) as input for a new query in one go, much like nested queries in SQL
– Stijn Sanders
Nov 26 '10 at 23:17
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PostgreSQL ERROR: canceling statement due to conflict with recovery
...is not modified is to suspend the replication and resume after the query:
select pg_xlog_replay_pause(); -- suspend
select * from foo; -- your query
select pg_xlog_replay_resume(); --resume
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Apply multiple functions to multiple groupby columns
... group. When aggregating, g will be a Series. Passing g.index to df.ix[] selects the current group from df. I then test if column C is less than 0.5. The returned boolean series is passed to g[] which selects only those rows meeting the criteria.
In [95]: cust = lambda g: g[df.loc[g.index]['C']...
What is the IntelliJ shortcut key to create a javadoc comment?
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Do I have to select something? Even if I select the whole file content or select nothing, nothing happens if I run this action. May I am missing something
– Honsa Stunna
Jun 18 '19 at 11:46
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Laravel 4 Eloquent Query Using WHERE with OR AND OR?
... ->orWhere('d', '=', $d);
})->get();
Will produce a query like:
SELECT * FROM <table> WHERE (a='foo' or b='bar') AND (c='john' or d='doe');
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Randomize a List
...uffle();
The code above uses the much criticised System.Random method to select swap candidates. It's fast but not as random as it should be. If you need a better quality of randomness in your shuffles use the random number generator in System.Security.Cryptography like so:
using System.Security....
What are the dark corners of Vim your mom never told you about? [closed]
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viwy or viwc. Yank or change current word. Hit w multiple times to keep selecting each subsequent word, use b to move backwards
vi{ - select all text in figure brackets. va{ - select all text including {}s
vi(p - highlight everything inside the ()s and replace with the pasted text
b and e move...
Installing Apple's Network Link Conditioner Tool
...per.apple.com/download/more/?q=Additional%20Tools
Install the dmg file, select hardware from installer
select Network Link conditioner prefpane
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How can I backup a remote SQL Server database to a local drive?
...er to perform a decent backup of your database, even on a remote server:
Select the database you wish to backup and hit next,
In the options it presents to you:
In 2010: under the Table/View Options, change 'Script Data' and 'Script Indexes' to True and hit next,
In 2012: under 'General', change...
Is it possible to group projects in Eclipse?
...You define a working set and then add some projects to it. Later you could select a working set and only the projects you selected earlier are shown in project explorer.
Simpl grouping to reduce clutter.
http://help.eclipse.org/galileo/index.jsp?topic=/org.eclipse.platform.doc.user/concepts/cworkse...